Skin is composed of epidermis, dermis, and subcutaneous tissue. While providing protection against an attack by microbes that are introduced form an outside, skin plays a very important role for maintaining body moisture and body temperature. Epidermis plays a role of protecting skin, regulating body temperature, and maintaining body moisture, and it is composed of an extracellular matrix which is related to skin elasticity and skin flexibility. Dermis is directly related with skin aging.
Upon binding to a receptor for an epidermal growth factor present on a surface of a cell, the human epidermal growth factor (hEGF) induces a dimerization of a receptor for an epidermal growth factor. A dimeric receptor for an epidermal growth factor activates the tyrosine kinase present in the receptor to induce an intracellular signal transduction system. As a result of those processes, glycolysis and protein synthesis are promoted in a cell, eventually leading to cell growth.
The epidermal growth factor playing an important role in skin regeneration decreases according to a progress of aging, and a decrease in the epidermal growth factor causes a reduction in skin cell proliferation and transfer, and thus phenomena like skin aging, increased wrinkles, and reduced skin elasticity are exhibited accordingly.
PnTx2-6 as one spider venom of a Brazilian wandering spider (Phoneutria nigriventer) is composed of 403 nucleotides which consist of many glutamates and signal peptides. PnTx2-6 is known to have an influence on a flux through a sodium ion channel and induce an erection in an anesthetized rat.
As a spider venom of a Brazilian wandering spider, 100 or more kinds of a polypeptide with a size of 3,500 to 9,000 Da are known. By inducing secretion of acetylcholine and glutamate in TTX (tetrodotoxin)-sensitive way, it increases the introduction of sodium ions into a cortical synaptosome, thus preventing inactivation of a sodium channel. Accordingly, a phenomenon of priapism is caused.
As one of the spider venoms of a Brazilian wandering spider which cause a phenomenon of priapism, PnTx2-6 has been continuously studied all over the world since 2010 as a natural protein which may be used as a substitute for Viagra. However, the accurate intracellular working mechanism of PnTx2-6 is not known yet, and there are only few studies that are known to be related to a large scale production of PnTx2-6 for its use as a natural protein which can substitute Viagra.
Meanwhile, in Korean Patent Registration No. 1613302, “SV82 polypeptide and a cosmetic composition for improving skin wrinkle and maintaining skin elasticity comprising the same as effective component” is disclosed. Furthermore, in Korean Patent Application Publication No. 2015-0056022, a “cosmetic composition for improving skin comprising fusion protein of epidermal grown factor” is disclosed. However, no description has been made for the thermostable human epidermal growth factor-spider venom fusion protein with increased skin cell proliferation effect and cosmetic composition for improving skin wrinkle and maintaining elasticity of skin comprising the same as effective component of the present invention.